Angle-resolved photoemission spectroscopy (ARPES) is a powerful tool of probing electronic structures in solids, however static ARPES fails to visualize ultrafast dynamic processes and interactions, which contain rich physical... [ view full abstract ]
Angle-resolved photoemission spectroscopy (ARPES) is a powerful tool of probing electronic structures in solids, however static ARPES fails to visualize ultrafast dynamic processes and interactions, which contain rich physical information, for example, light-matter interaction and electron coupling with various coherent collective modes, which survive in few picoseconds or even tens of femtoseconds. To directly study such interesting phenomena, it is critical to develop time-resolved ARPES (TR-ARPES), by implementing ultrafast pump-probe laser beams: a first low energy infrared (IR) pulse as pump to stimulate/drive the system, and then a second high energy ultraviolet (UV) or extreme ultraviolet (XUV) pulse as probe to detect transient electronic states from femtosecond to picosecond time-scales.
Here I will first briefly introduce the development of a high resolution TR-ARPES, based on NIR/MIR pump and XUV probe. Then I will talk about its applications with two different hot topics: Photon-driven insulator-to-metal electronic transition and detection of collective modes in charge-density-wave (CDW) materials.
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